Temperature-regulator for furnaces.



H. E. GILBERT. TEMPERATURE REGULATOR FOR FURNACES, APPLICATION FILED 056. 9, 1914.

Patented AprJi, 1916.

WITNESSES W 'NVENTOR under a slight pressure but permit the cooler stantly escaping as hotter gases rise up into the casing to take their place. It will thus be apparent that an increase in the temperature of these gases above the predetermined required temperature brings the thermostat into operation to oiose or partly close the valve 5 so that the supply of fuel to the main burners 4 is correspondingly cut down, therefore resulting in a lowering of the temperature in the furnace chamber. In case the temperature of the furnace gases drops below the required temperature the reverse of the foregoing conditions takes place, the valve 5 being then opened, and a greater amount of gas fed to the burner.

By the construction described, itis mam-- fest that the exceedingly high temperature of the furnace maybe regulated without inserting the thermostatic element-into it, and this is so because the small portion of the gases which are allowed to pass to the casing containing the thermostatic element are so governed that changes in its temperature are proportional. to the changes in temperature of the gases within the furnace itself. The.

thermostatic element could not withstand the hightemperature of the furnace, but by my improvements it is enabled to accurately cause the regulation of the temperature of the furnace itself.

In order to vary or change the fixed temperature of the furnace I have provided a means for cutting down or increasing, as the case may be, the quantity of heated products so that the thermostat operates in a different timed relation. This means, in the present instance, consists of a regulating slide bar 11, preferably tapered longitudi nally and. adapted to seat and have sliding movement within openings 12 located respectively at opposite sides of the casing 7 In order to properly guide this bar itis provided with a flange l3 seating within a grooved portion 14: of the casing, so that the bar is accurately centered and positioned for effective work. A. lug 15 may be pro vided at one end of the rod to prevent the said rod from being completely withdrawn or detached from the casing 7. The operative position of the bar 11 is between the port 8 and the end of the thermostatic ele ment so that in effect it serves the purpose of a bafiie or cut-ofi' to deflect the gaseous products outwardly toward the side of the casing 7 and away from the thermostatic element. This bar 11 also acts in a measure as a valve to restrict the upward flow of the hot gases for it reduces or increases the area a of the passage within the casing 7 accord ing to its adjustment. In case the bar 11 is drawn out to its fullest extent the small tapered end thereof is interposed between the port 8 and the thermostatic element and the maximum freedom of supplyfof heatedf productsthrough the casing 7 intocontaotx with the thermostatic element 6 is permit-. ted.. As the bar is'moved inwardly ,this freedom of supply is gradually out down: until the bar reaches the position where its widest portion is interposed, at which time a minimum freedom of supply of the gas products into the casing 7 and around the thermostatic member is permitted. The hot gases which pass'up into the casing 7 ul'timately pass out through the small openings extent than when the hot gasesare permitted a more free passage upward and into more direct contact with the thermostatic element. In order to accurately detern'iinev the position of the slide bar 11 for different controlling temperatures I have preferably graduated an extension of the same, as shown at 16, to represent temperature element is affected to a correspondingly less changes and also provided an indicator lZ-. suitably mounted upon a fixed part of the furnace and extending into operative rela-. tion to theslide bar ll, as will be under:

stood.

In starting the heating of the furnace it may be des ired to/ sup'plythe gas to :the burners 4: regardless of any regulation, and for this purpose I have provided a by-pass 18, around thecontrol valve 5, said bypass having a hand controlled valve 19 therein. so that it may be used when desired. When 1 the furnace is heated, the by-pass-valve 19 may beshut off and the furnace temperature then regulated by use of my thermostatic improvements.

It may be desirable in some instances, more especlallywhere the furnace tempera-; ture is very high, to provide a means for more sensitively controlling the actuation of,

the thermostat and consequently varying the. supply of gas .more promptly. In the present instance I have shown in Figs. 8 and t such a means, wherein 20 designate-s an open-i ing through the wall of the casing 7 and looated adjacent the lower end thereof, which: I opening is adapted to be controlled by a slide valve 'member 21." This valve member.

is suitably mounted for sliding movement. in

the guides 22, and atone end is connected:

to a bell crank 23 which is actuated by the I rock spindle 24.' Motion is transmitted to,

the spindle 2. by means ofa crank arm 25 having its opposite end secured to the rod 11 as shown at 26. It will thus be apparent. that movement ofthe rod in one direction or the other will simultaneously raise or lower the slide valve 21 and thus act to open.

or close the opening 20. The adjustment of these parts is such as to cause a proportionate regulation of the opening 20 relative to the position of the control slide bar 11. In

.this case the rising heat products are deany other suitable form and manually adjusted by any other operative means in lieu of that shown. If there is an overabundance of heat in the gases from the furnace, the objectionable excess may be allowed to es cape from the casing 7 through the opening 20, so that an excessive heat will not reach the thermostatic member. By employing this valve controlled opening, the regulation is effected more rapidly and hence the temperature of the furnace is more constant. By this construction it is obvious the temperature of the furnace may be quickly changed from one temperature-to another, after which conditions are promptly returned to normal so that the desired temperature may then be maintained substantially constant.

In the operation of the device, to maintain the predetermined temperature, the slide bar 11 is manually moved to the position desired to impede and deflect to the proper extent the heated products passing through the thermostat casing 7, in accordance with the required regulation for the temperature to be maintained in the furnace. Having effected this adjustment, the device automatically controls and regulates the heat to the thermostatic element so that the heated furnace is maintained at the required constant temperature. Should this temperature be exceeded, owing to an excess amount of gas being supplied to the burners 4, the rise in the temperature of the hot products passing through the casing 7 will causethe thermostat to expand and thus operate the valve 5.to cut down thesupply to the burners. Under reverse conditions, that is, a lowering of the temperature, the thermostat contracts so that the valve 5 is opened and thesupply of gas to the burner 4 correspondingly increased. in this the predetermined temperature is ma1ntained substantially constant wi thin the furnace; and this desired temperature be higher or lower as required by simply adjusting the bar 11 to suit the requirements. As before pointed out, this regulation may be supplemented by controllin the opening 20 by the valve 21 to make the apparatus more sensitive, especially in cases Where the furnace temperature is high. By permitting a continual escape of the hot gases from the opening 20 and causing a relatively less volume to pass to the tuermosta element 6, the latter 'ivill be more sensitive to temperature changes and the resulting regulation -Wlll be more responsive andthc i'naintenance of the temperature more constant.

While I have referred to pipe 3 a gas pipe it may be employed. to supply oil to the burners and therefore it may be considered a fuel pi pe, irrespective of the character of fuel employed. 7

It will now be apparent that I have devised a complete unitary structure suitable for a furnace, and wherein the parts are automatically controlled to maintain a constant temperature in the furnace, and further more, in which this constant temperature may be maintained at a higher or lower degree at Will by adjusting the location of the slide bar 11 to meet the conditionsdesired.

In this application no claim is made to the method of operation herein described, as the same iYS"'ISBiYGl for a separate application.

Having now described my invention, What I claim as new and desire to protect by Let ters Patent is 1. In a device of the character stated, a furnace in combination with a casing having communication with the combustion chamber of the furnace to provide for a restricted circulation of a portion of the heated products therefrom through said casing, a thermostat mounted in said casing, afuel supply pipe operatively connected to the burners of said furnace, a valve in said fuel pipe and controlled by said thermostat, and means for varying the quantity of heat passing through said casing in contact with the thermostat by deflecting a portion of heated products out of the circulation before reaching the thenmostat.

:2. In a device of the character stated, a furnace in combination with a' casing hav ing communication with the combustion chamber of the furnace to provide for a re stricted circulation of a portion of the heated products therefrom through said casing, a. thermostat mounted. in said casing, a fuel supply pipe operatively connected to the burners of said furnace, a'valve in said fuel. pipe controlled by said thermostat, and an adjustable regulating valve device between said thermostat and the inlet for the heated products to said casing for releasing a portion of the heated products to a point outside or the casing and thereby varying the quantity of heat passing through said casing in contact with the thermostat, Whereby the temperature of said furnace may be regulated according to requirements.

3. In a device of the character stated, the

combination of a furnace, a fuel supply therefor, means controlled Wholly by the temperature of the heated products from said furnace and independent of atmospheric conditions constant temperature in said furnace, and

manually controlled devices to deflect a portion of the heated products from said means into the atmosphere for changing the predetermined. temperature of the furnace to be maintained,

l. In a device of the character stated, a furnace combined with a casing having communication with the combustion chamber of the furnace to provide for a restricted circulation of a portion of the heated products therefrom through said casing, said casing also being provided withvside openings arranged in alinement and located adjacent the lower and inlet portion to said casing, athermostat mounted in said casing above said openings, a fuel supply pipe operatively connected to the burners of said furnace, a

valve in said. pipe controlled by said thermostat, and a tapered bar slidably'mounted in said casing openings and arranged below the thermostat to deflect and retard the circulation of theheated products.

5. In a device of the character stated, a

furnace, in combination with a casing having commrm'ication with the combustion chamber of, the furnace and providing a restricted circulation of a portion of the heated products therefrom through said casing, a thermostat mounted in said casing at its upper portion, means to supply fuel to the furnace, means to regulate the supply of fuel controlled by the thermostat, and adjustable means for causing a portion of the heated products to be removed away from the thermostat, whereby the thermostat is ailected wholly by the heated products from the furnace to a greater or less predetermined degree and unaffected by the varying atmospheric changes of temperature.

6. In a device of the character stated, a furnace, in combination with a casing separate from the furnace and entirely out of the general circulation of the products of combustion thereof and having a conduit leading therefrom to provide a restricted circulation of a relatively small quantity of a heated medium through the casing said medium of relatively low temperature and deriving its heat from the furnace and of a temperature greatly below that of the furnace, a thermostat mounted in said casing and under the influence of the relatively low temperatureheated medium having the restricted circulation within said casing, means to regulate the heat or the furnace controlled by the thermostat, and manually controlled adjustable means for changing the speed of restricted circulation of them) low temperature heated medium about the thermostat, whereby the temperature of the furnace may be predetermined and'maintained constant.

7. In a device of the character stated, a

furnace, in combination with a casing out side of the furnace proper but having com, munication therewith to provide'fon a restricted circulation through the casing of a small quantity of heated gaseous medium deriving itsheat from the furnace, a thermostat mounted in said casing, means' controlled hy the thermostat to regulate the fuel supply to said furnace to maintain a substantially constant temperaturetherein,

manually controlled means, and adjustable means actuated by the manually controlled means for changing the predetermined temperature of the furnace which is to be maintained said adjustable means comprising defor the products of combustion therefrom so as to have a relatively low temperature but through which casing a small quantity of a heated gaseous medium deriving its heat, from the furnace is'circulated, a thermostat mounted in the casing and subjected to the heat of the circulating gaseous medium but 1 wholly removed fromthe high temperature of the circulatory system of the heated prodnote from the furnaca mean controlled by the thermostat to regulate the fuel supply to the furnacejand means for diverting a portion of the heated gaseous medium re-' ceived from the furnaceto a point outside of th casing before it reaches the thermostat for controlling the speed :of circulation of i the Heated gaseous medium in contact with i the thermostat, whereby the temperature of the furnace may be predeterminedand maintained constant.

In testimony of which invention I hereunto my hand.

, HARRY E. GILBERT. f

Witnesses: I

FLORENCE Deacon. 

